Histochemical evidence for lipoidal material in secretory granules of rat salivary glands

Synposis The granules of parotid acinar cells and submandibular granular tubule cells of rats contain one or more periodic acid-Schiff positive substances that are extracted during fixation with lipid solvents or acidic solutions or if frozen sections are stained in aqueous solutions. The granules in these cells can be stained by Schmorl's reaction, Luxol Fast Blue and a permanganate-Aldehyde Fuchsin sequence. The results obtained with these stains after a variety of fixation procedures strongly suggest that the secretory granules of these two cell types contain several components and that in parotid acinar and submandibular granular tubule cells, at least one of these components is a lipoidal substance.